BUSINESS ACQUISITION (Pro Forma) (Details) (Solstas Lab Parnters Group [Member], USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Solstas Lab Parnters Group [Member]
Business Acquisition [Line Items]
Pro forma net revenues	$ 1,815	$ 1,886
Pro forma income from continuing operations	$ 110	$ 123
Earnings per share attributable to Quest Diagnostics’ common stockholders - basic:
Pro forma income from continuing operations	$ 0.71	$ 0.73
Earnings per share attributable to Quest Diagnostics’ common stockholders - diluted:
Pro forma income from continuing operations	$ 0.70	$ 0.72

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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